This proposal seeks to build on 4 years of funded work on the ethical, legal, and social implications (ELSI) of genetic research in American Indian and Alaska Native (AI/AN) communities. In the course of that work, questions of trust have emerged with unique salience as American Indian and Alaska Native community members have expressed concerns with abusive treatment by researchers whom they characterize as primarily interested in self advancement and who, it is argued, have returned little of value to these communities that suffer so disproportionately from health disparities. These concerns have been raised with particular acuity in the context of genetic research on complex disorders such as diabetes and alcohol dependence - problems for which genetic contributions have proven to be much more difficult to discern than originally hoped and for which environmental and behavioral interventions continue to show the best promise. As we have surveyed the extant ELSI literature for other populations, we have been struck by the degree to which many of the concerns we have heard in AI/AN communities are raised elsewhere. We focus, here, on cancer genetics instead of the more easily critiqued work in diabetes and alcohol dependence because it is in this area that the promise of personalized medicine may first be realized. Cancer genetics thus provides us with what is arguably a much stronger basis for exploring the possible benefits and risks of genetic knowledge in biomedical research and health care. We have three specific aims: 1. to explore attitudes toward genetic knowledge, research, and health care for cancer in four urban cultural communities; 2. building on these discussions, to articulate the sources of both trust and mistrust toward research in these communities; and 3. to work collaboratively with community members and organizations to identify policies and procedures that can address sources of mistrust and strengthen trust in possible future genetic research and health care.